Advertisements
Advertisements
प्रश्न
The area of a circle is given by the expression πx2 + 6πx + 9π. Find the radius of the circle.
Advertisements
उत्तर
We have,
Area of a circle = πx2 + 6πx + 9π = π(x2 + 6x + 9)
⇒ πr2 = π(x2 + 3x + 3x + 9) ...[∵ Area of a circle = πr2, where r is the radius]
⇒ πr2 = π[x(x + 3) + 3(x + 3)] = π(x + 3)(x + 3) = π(x + 3)2
⇒ πr2 = π(x + 3)2
On comapring both sides, r2 = (x + 3)2 ⇒ r = x + 3
Hence, the radius of circle is x + 3.
APPEARS IN
संबंधित प्रश्न
Simplify (ab + bc)2 − 2ab2c
Simplify (m2 − n2m)2 + 2m3n2
Using identities, evaluate 78 × 82
Using identities, evaluate 8.92
Expand: (2x + 3y)2
Expand the following square, using suitable identities
(mn + 3p)2
If a + b = 10 and ab = 18, find the value of a2 + b2
(a + b)2 = a2 + b2
The area of a square is 9x2 + 24xy + 16y2. Find the side of the square.
If p + q = 12 and pq = 22, then find p2 + q2.
